// 24 x 24
const unsigned char air_filter_24x24[] PROGMEM = {
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  0xff, 0xc0, 0xff, 0xff, 0x02, 0x7f, 0xfe, 0x7e, 0x7f, 0xfe, 0x7e, 0x7f,
  0xfe, 0x7e, 0x7f, 0xf6, 0x70, 0x4f, 0xf6, 0x7c, 0x1f, 0xfe, 0x72, 0x7f,
  0xf6, 0x78, 0x0f, 0xf6, 0x7e, 0x3f, 0xfe, 0x70, 0x6f, 0xf6, 0x78, 0x0f,
  0xfe, 0x7e, 0x7f, 0xfe, 0x7e, 0x7f, 0xfe, 0x40, 0xff, 0xff, 0x03, 0xff,
  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
};